Mathematical Methods and Models for Economists

Much of the time of the average graduate student in economics is spent learning a new language, that of mathematics. Although the investment does eventually pay off in many ways, the learning process can be quite painful. I know because I have been there. I remember the long nights spent puzzling over the mysteries of the Hamiltonian, the frustration of not understanding a single one of the papers in my second macroeconomics reading list, the culture shock that came with the transition from the undergraduate textbooks, with their familiar diagrams and intuitive explanations, into Debreu's Theory of Value, and my despair before the terse and incredibly dry prose of the mathematics texts where I sought enlightenment about the arcane properties of contractions.

This book is an attempt to make the transition into graduate economics somewhat less painful. Although some of my readers may never believe me, I have tried to do a number of things that should make their lives a bit easier. The first has been to collect in one place, with a homogeneous notation, most of the mathematical concepts, results, and techniques that are required to follow the standard first- and second-year theory courses. I have also tried to organize this material into a logical sequence and have illustrated its applications to some of the standard models. And last but not least, I have attempted to provide rigorous proofs for most of the results as a way to get the reader used to formal reasoning.